Compressed air brake with stage braking



April 25, 1933. w. HoTz 1,905,155

COMPRESSED AIR BRAKE WITH STAGE BRAKING Filed April 8, 1930 2Sheets-Sheet 1 April 25, 1933.l W. HOTZ coMPREssED AIR BRAKE WITH STAGEBRAKING Filed April 8, 1930 2 Sheets-Sheet 2 Patented Apr. 25, 1933UNITED STATES WILHELM HOTZ, F BASEL, SWITZERLAND comrnnssnn Ain BRAKEWITH STAGE BRAKING `AppIication led Api-i1 8, 1930. ySerial No. 442,611.

m provided on the railway car coming into contact lwith stops.

The object of the present invention is to eliminate the disadvantages ofknown systems by providing an improved apparatus in 15 which the brakingaction comes into operation in stages but at an adjustable speed andwith an adjustable force. A Vfurther object of the invention is toprovide improved means by which the emergency arrangement 2 isdisengaged automatically when the engineer effects the brakingoperation. Y The installation according to the invention also has thefurther advantage that the emergency brakeis brought into operationautomatical- 25 ly when the engineer by reason of accident,

ill health or death etc. loses control of the train and no longercontrols the brake arrangement. j

In the accompanying drawings an exam- 3 ple of construction isillustrated diagrammatically in Figs. 1 and 1a.

Figs. 2 `and 3 show the controlling valve in sectional elevation and ina top view respectively Figs. 4 and 5 show in sectional elevation and ina cross-sectionV the auxiliary valve.

In the underframe 1 of the vehicle a roller 2 is vertically movableA insuitable guides by means of bearings. The said roller 2 is 4 mounted insuch a position that it can run on a brake actuating cam rail 3 mountedinthe track.- The rail 3 is adjustable vertically to cause theroller-2to move upward in the guides 1 when running on said l 45 rail.The bearing of the roller 2 is connected by a link parallelogram 4, 5 toa stationary in 6 oi the underframe. A spring 7, connected to the`members 5, tends to press the roller 2 downwardly.` The parallelogramis 0 connected by means of a rod 8 to the arm 9 pipe) and the driversbrake valve (26) to of a cock 10 of a compressed air pipe 11. The pipellis connected to the pipe 12, which pipe is connected to the compressedair supply pipe of the. train. The brake mechanism shown is of the Wellknown Westinghouse .55 type, and istherefore not described in detail.

To the pipe 11 is connected the lower end of a cylinder 14 provided withtwo chambers 15 and 16 separated by a partition provided with arestricted opening 17. TheV lower 60 chamber 16 is partly iilled with aliquid.

In the VVlower chamber 16 is provided a coiled spring 18 of which oneend bears against the partition and the other end against a piston 19having a rod 20. The spring 18 tends to press the piston 19 downwardlyand to'hold it in the position shown in the drawings. 1

The upper portion of the piston rod 20 has a rack engaging a toothedwheel 21, the latter being rigidly connected to a rotary valve disk 23which controls the air outlet openings 28 of a casing v22. The latter isconnected by a compressed air pipe 25 (main the compressed air brakeinstallation 27 of the train. The rotary valve 23 is provided with slots28 of unequal length and unequal radial distance. When the rotary valve23 is turned,air passes out of slots 29 of casing 22 and therefore outof the pipe 25 and `thus further out of the brake arrangement 27 of thetrain. The outflow of air and hence also the braking action is effectedin stages because the airV escape is interrupted except when thedifferent air outlet openings 28 register with and pass over theircorresponding slots 29. The actuation movement of the `brake blockstherefore is interrupted for short intervals a number of times, and inthis '90 manner the usual braking operation effected by hand(balancing'the compressed "air in the main pipe) is imitated. Y

To the valve 26 are connected in known manner the cylinders 30 servingto adjust the brake blocks.

There is also provided a further cylinder 31, the piston rod 32 of whichby means of a lever`33 and links 34 secured to the bearing of the roller2, can raise'the bearings ofthe 1100 roller 2 and thus move said rollerout of its position in readiness for operation. The discharge ofcompressed air by the valve 26, causes the cylinder 31 to operateelements 32, 35 and thereby raise the roller as will be understood. Itthe engineer by means of the brake valve 26 applies the brakes of thetrain the arrangement 11-25 does not come into operation because owingto the position of the brake valve 39 the, connection between the pipes12 and 11 is interrupted.

The connection of thisauxiliary device 14 to valve 29 is effected forexample in the case of the Westinghouse drivers brake valve 26 by meansof the pipe 12 which is attached at the existing blind socket member 50adjacent the usual pressure regulator. Said valve is also attached totheV air tank 27L as usual. On the drivers brake valve 26 of theWestinghouse rapid brake there is in accordance with this invention madea modiiication by which the pipe 12 also communicates with the main airtank 27b by the pipes 27, when the handle 51 of the valve 26 moveswithin its filling position, denoted by the numbers I, Il (Fig. 3). Thismodification consists in that opening 33 (which in the standardconstruction of the Vestinghouse valve is only a circular port) isconverted into an elongated slot, as shown, so that the pipe 12 throughthe connection 50 and hence also the whole auxiliary device according tothis invention communicates with the supply mains of compressed air ofthe installation throughout the period in which the engineer moves thehandle 51 of valve 26 between the limits I, II. The said communicationis interrupted as soon as handle 51 is moved into the braking positionITI of valve 26, or into the emergency position IV-V, because the slot53 is then out of communication with the pipe 12.

Between the pipe 12 and the pipe 11 there is provided a by-pass pipe 38itted with a valve 39, which is normally held in closed position by asuitable spring (not shown). Said valve may be actuated manually bymeans of a hand lever 40 and a pedal 41. This arrangement serves as asubstitute for the socalled dead mans lever. Tf the engineer releasesthe lever 40 and pedal 41 for any reason the by-pass pipe 38 is opened,compressed air from the pipe 12 passes into the cylinder 14 and thebrakes of the vehicle and thus of the train are then appliedautomatically by the piston 19, cylinder 14, auxiliary valve 22 andtheir connections, hereinbefore described and as will be understood.

There is also provided a rod mechanism 42 connected to the trolley 43and to a cock 44 in order to lower the trolley 43 when the emergencyarrangement operates, as a result of which the locomotive is cut out ofcircuit and when travelling into a station transmission of current fromthe line section to station mains cannot take place.

As soon as the engineer moves his brake valve 26 into the filling orreleasing position the auxiliary device 14 again returns to its positionready for operation because the spring 18 forces the piston 19downwardly to the normal position shown in Fig. 1, owing to the reducedair pressure below the piston incident to such operation of theengineers valve.

The adjustment of the brake actuating rail 3 may be effected in anysuitable manner. It may be connected to the usual signal settingmechanism and it may also be released by any other suitable distantoperation. Further the rail 3 may also be set by the trains themselvesby means of setting bars in order to thus obtain a block safety. fllhenthe roller 2 runs onto the set rail the roller is raised against theaction of the spring 7 and the valve 10 is opened by means of theparallelogram links 4, 5, the rod 8 an-d the member 9. Compressed airenters the cylinder 14 below the piston 19. The latter is moved againstthe action of the spring 18. Liquid is thus forced through the opening17 in the partition. The piston moves more slowly or more rapidlyaccording to the size of the opening in the partition. The rotary valve23 is therefore turned at a select-ive speed. In this manner the brakingaction is also predetermined as regards time and power. To the rod 20may also be connected a switch 46 of a circuit 45 controlling thedriving motors (releasing coil) for example in such a manner that thelatter are disconnected from the drive before the braking actioncommences.

What 1 claim and wish to secure by the U. S. Letters Patent, is

1.111 air rbrake apparatus, a brake pipe, fluid pressure actuatedapparatus connected thereto and including a movable element, anengineers valve, and an emergency valve including a casing connectedpneumatically with the engineers valve for the discharge of air from thelatter, and also including an element actuated by the movable element ofsaid fluid pressure apparatus, said emergency valve being constructedand arranged to successively and intermittently ldischarge compressedair from the brake apparatus through the engineers valve during a singlemovement in one direction of the said movable element of the sai-d fluidpressure actuated apparatus, and means, independent of the engineersvalve to establish communication between the said brake pipe and saidtluid pressure actuated apparatus, to cause the latter to operate andhence cause the brakes to be applied by the emergency valve in the eventof failure of operation of the engineers valve.

2. Apparatus as claimed in claim 1, including a ixed prime moving trackmember and train carried means including a member actuated by said primemoving track member to automatically supply compressed luid to saidvalve actuated means.

3. Apparatus as claimed in claim 1, in which the fluid pressure actuatedmeans is a cylinder to which the brake pipe is connected and having apartition provided with an opening, a piston in said cylinder below saidpartition and coacting with the cylinder to form a fluid containingchamber to retard the valve actuating stroke of the piston.

4. Apparatus as claimed in claim 1, in which the iluid pressure actuatedmeans is a cylinder to which the brake pipe is connected and having apartition provided with an opening, a piston in said cylinder below saidpartition and coacting with the cylinder to form a fluid containingchamber to retard the valve actuating stroke of the piston and alsoincluding a spring active to impart reverse stroke to the piston.

5. Apparatus as claimed in claim 1, in which the emergency valvecomprises a casing having an air exhaust port and a plurality of airsupply ports and also inclu-des a revoluble valve disc having aplurality of ports arranged to successively come into registry with theair supply ports of the casing.

6. Apparatus as claimed in claim 1, including means to automaticallysupply compressed uid to the fluid actuated means and also including anengineers valve connected to the air brake system and also connected tothe first named valve, said engineers valve being constructed andarranged to automatically cut out connection between the irst namedvalve and the brake pipe when the engineers valve is moved to brakingposition or to emergency position.

7. Apparatus as claimed in claim 1, including a fixed prime movingmember and train carried means including a member actuated by said primemoving member to automatically supply compressed fluid to said valveactuated means and also including an engineers valve and compressed iuidactuated means controlled by the engineers valve to move the traincarried member to inoperative position In testimony whereof I affix mysignature.

WILHELM HOTZ.

